After 18 years as chairman of the state Democratic Party, it was over in a moment Saturday for Mark Brewer.

“I’ve had a great 18 years as chairman of the Michigan Democratic Party and I’ve enjoyed working with all of you,” Brewer said minutes after the business of the convention began. “But I’m withdrawing my candidacy for chairman.”

Almost immediately, more than 3,600 Democratic delegates attending the party’s state convention at Cobo Center in Detroit, unanimously elected by acclimation Kalkaska Democrat Lon Johnson as the party’s next chairman.

“I know this has been a spirited campaign, but we’ve always admired what (Brewer) has done for our party,” Johnson said. “We must stand together, because it’s the only way to win.”

The sea change at the top of the party represents a shift from the old-time politics that Brewer grew up in, starting in Macomb County, to the digital era that Johnson, who is married to Julianna Smoot, deputy campaign director for President Barack Obama, represents.

After his election, Johnson asked the delegates to take out their smart phones, take a picture and post it on Facebook and Twitter with the #ThisisMichigan hashtag.

Johnson, 41, is known as an effective fund-raiser and part of a new generation of Democratic leaders. He narrowly lost a race for state House in November in a highly Republican, northern Michigan district.

He had a wide range of support from the powerful – UAW and Teamsters and Michigan’s Democratic congressional delegation in Washington – and the grass roots communities of young Democrats, the LGBT community and many of the African American caucuses.

Brewer’s base of support among local party leaders, the teachers’ organizations and several other large unions, wasn’t enough to stop Johnson’s momentum.

But it wasn’t a pretty or easy journey.

A nasty credentials fight Friday night went Johnson’s way, but it burst into a heated exchange Saturday between U.S. Rep. Sander Levin, D-Royal Oak and a Johnson supporter, and Ed Bruley, Macomb County Democratic Party chairman and a Brewer supporter.

Levin accused the Brewer camp of lying and Bruley said the UAW was muscling its way into sustained power by rigging the rules.

“It’s not fair when a major organization wants to dominate so heavily that they change the rules because they have the votes at a particular meeting,” Bruley said.